Inferring speaker attributes in adductor spasmodic dysphonia: ratings from unfamiliar listeners

To determine whether unfamiliar listeners' perceptions of speakers with adductor spasmodic dysphonia (ADSD) differ from control speakers on the parameters of relative age, confidence, tearfulness, and vocal effort and are related to speaker-rated vocal effort or voice-specific quality of life.

Twenty speakers with ADSD (including 6 speakers with ADSD plus tremor) and 20 age- and sex-matched controls provided speech recordings, completed a voice-specific quality-of-life instrument (Voice Handicap Index; Jacobson et al., 1997), and rated their own vocal effort. Twenty listeners evaluated speech samples for relative age, confidence, tearfulness, and vocal effort using rating scales.

Listeners judged speakers with ADSD as sounding significantly older, less confident, more tearful, and more effortful than control speakers (p < .01). Increased vocal effort was strongly associated with decreased speaker confidence (rs = .88-.89) and sounding more tearful (rs = .83-.85). Self-rated speaker effort was moderately related (rs = .45-.52) to listener impressions. Listeners' perceptions of confidence and tearfulness were also moderately associated with higher Voice Handicap Index scores (rs = .65-.70).

Unfamiliar listeners judge speakers with ADSD more negatively than control speakers, with judgments extending beyond typical clinical measures. The results have implications for counseling and understanding the psychosocial effects of ADSD.